adjusting more padding and visual space for response area

apps/openassessment/xblock/static/sass/oa/views/_oa-base.scss

@@ -498,7 +498,7 @@
     .response__submission {
       margin-top: ($baseline-v*2.5);
       position: relative;
-      padding: ($baseline-v*1.5);
+      padding: ($baseline-v*0.75);
       background: $color-decorative-tertiary;
       border-radius: ($baseline-v/10);
     }